Experimental study of water-based nanofluid alternating gas injection as a novel enhanced oil-recovery method in oil-wet carbonate reservoirs

摘要

Water-alternating gas injection (WAG) is a common EOR method used at different reservoirs around the world. In this paper we present a novel method called a nanofluid alternating gas (NWAG) injection to improve the ability of the conventional WAG process for the oil-wet carbonate reservoirs. Different experimental tests of water-alternating gas (WAG), as well as nanofluid alternating gas (NWAG) injection were performed on carbonate core samples saturated with crude oil. SiO2 nanoparticles, with spherical morphology and two different sizes of 11-14 and 30-40 nm, were used to improve the performance of the WAG injection method. The WAG process in the core-flooding experiments was carried out by the injection of gas and SiO2 water-based nanofluids. Also, different characterization investigations, such as interfacial tension and contact angle measurements, were completed to study the nanoparticles effect on the recovery mechanisms.